1. Field of the Invention
The invention relates to a method of manufacturing a hollow spindle that serves, in particular, as the mounting for valve-actuating levers that control exhaust-and-intake valves in an internal combustion engine.
2. Description of the Prior Art
A hollow spindle, specifically a rocker lever spindle of the aforementioned type, is known from DE 42 21 708 A1. This rocker lever spindle consists of an outer tube, in the interior of which a shaped tubular body is fixed. By means of the tubular body, which has a longitudinal rib, at least two and preferably three liquid-carrying chambers are formed. In a special embodiment (FIG. 2), the tubular body has a roughly V-shaped cutout that extends in the longitudinal direction to form a chamber. The tubular body is pushed or pressed into the outer tube and fixed in place by cam-type elevations or shapings on the mantle of the tubular body. A disadvantage of this design is that there is no assurance that the fixed position of the tubular body will be maintained or that the chambers will remain sealed under operating conditions. Furthermore, the lengths that can be manufactured are limited, so that production costs are high.
U.S. Pat. Nos. 3,863,328 and 4,125,924, disclose a method for fitting two tubes together in a rattle-proof fashion. After one tube is slipped into the other with a certain diameter clearance, a drawing point is formed on one end of the tubes. The tubes are then cold-drawn one atop the other.